Question

Roots of the quadratic equation $2x^2+2x-144=0$ will be

• A. imaginary and equal
• B. imaginary and distinct
• C. No real roots
• D. real and distinct

Answer 1

The correct option is D real and distinct

$2x^2+2x-144=0$

Comparing it with standard equation $a{x}^2+bx+c=0$

a = 2, b = 2, c = -144

D = <!--td {border: 1px solid #ccc;}br {mso-data-placement:same-cell;}--> $\sqrt{b^2-4ac}$

= $\sqrt{2^2-4\left(2\right)(-144)}$

= <!--td {border: 1px solid #ccc;}br {mso-data-placement:same-cell;}--> $\sqrt{4+1152}$

= <!--td {border: 1px solid #ccc;}br {mso-data-placement:same-cell;}--> $\sqrt{1156}$ = 34

So, D > 0
It mean roots will be real and distinct